Fluid to fluid heat exchangers find extensive use in both domestic and industrial applications and may be configured to provide a heating and/or a cooling effect as required.
Typically, a heat exchanger is constructed from a material of high thermal conductivity, in particular a metal, and comprises an internal chamber or network of chambers in which a heat transfer fluid is stored and allowed to flow. One example of a conventional heat exchanger is the domestic wall mounted radiator. In this example, water is heated by a remotely positioned boiler with the heated water then being transferred to the radiator via piping. The heated water then flows within the internal chamber(s) of the radiator transferring heat to the radiator body and ultimately the surrounding air.
Slightly more sophisticated heat exchangers operate under the same fluid to fluid heat transfer principle and are constructed from individual modular units which when assembled together form a single heat exchanger. Typical examples of modular heat exchangers are disclosed in U.S. Pat. Nos. 5,228,515, 4,742,866, 5,660,228, 5,392,848, 4,401,155, FR 2515805, EP 0252019 and EP 0239672.
Whilst known modular heat exchangers have a number of advantages including ease of transportation and installation prior to use, there are a number of significant disadvantages.
One problem with known modular heat exchangers is there limited construction versatility. Typically, the shape and size of the heat exchanger, constructed from the individual modular units, is limited. A further problem is the inherent difficulty in assembling the modular units to form the heat exchanger and subsequent full or partial dismantling when repair work is required.
A further significant problem with the construction of the heat exchanger from individual known modular units is the effectiveness of the heat exchanger to transfer heat, this being due to the non-optimised resulting heat exchanger shape and configuration.
U.S. Pat. No. 5,303,770 discloses a modular heat exchanger being formed from a plurality of elongate extruded aluminium blocks. Each module has a generally rectangular cross-section with a through bore extending between each end of the extruded block. Openings are provided at either end of each block such that when the modular units are stacked together the openings of neighbouring blocks are aligned providing internal fluid communication between the heat exchanger units.
GB 2365114 discloses a modular constructed radiator for a central heating system comprising a plurality of pipes and releasable push-fit coupling members configured to connect each pipe together to form a frame. Each push-fit coupling comprises at least two sockets, each having a pipe received therein and sealing means interposed between each-socket and the pipe to prevent egress of fluid from the frame via the coupling members.
Whilst the modular units of U.S. Pat. No. 5,303,770 and GB 2365114 provide for the construction of a modular heat exchanger, there is still a need for a modular unit that is more easily manufactured and in turn provides a stronger, more robust modular heat exchanger.